U.S. health insurance premiums rose 5 percent on average this year and more companies shifted an additional share of the cost to workers, an annual survey of businesses said on Wednesday.

The average premium for a family's health insurance provided by an employer rose to $12,680. Employees paid $3,354 of that cost on average, according to the survey by the nonprofit Kaiser Family Foundation and the Health Research & Educational Trust.

The 5 percent increase was similar to the previous year's rise and was lower than other annual gains. Still, premiums have more than doubled since 1999 while workers' wages grew 34 percent, researchers said.

Sixty-three percent of employers offered health benefits in 2008, similar to the 2007 rate.

More insured workers, however, paid higher deductibles this year as companies struggled with rising costs and put more of the burden on employees. Eighteen percent had a deductible of at least $1,000, up from 12 percent the previous year.

"Health insurance is steadily becoming less comprehensive," Kaiser President and Chief Executive Drew Altman said.

The growth in high-deductible plans mainly came from small businesses with fewer than 200 employees, the survey said. More than a third of those workers had to pay at least $1,000 out of pocket before their insurance generally kicked in.

New high-deductible plans have been touted as a way to curb a steady rise in health-care costs. They are often labeled "consumer-directed" because patients have more control over spending, but tend to bear more costs with higher deductibles.

The findings were based on polls of more than 2,000 randomly selected companies between January and May 2008. Results were published in the journal Health Affairs.

(Reporting by Lisa Richwine; Editing by Maureen Bavdek)

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